Research On Long Distance Communication Combining LoRa With Multi-hop Network

With the increasing application of Io T in practice,users’ demands for Io T are also changing.LPWAN has been find because of the trend on low power consumption,low cost,high number of access nodes,and wide communication coverage.Thesis takes a pre research project as the background and conducts the following research on low-power communication technology.Comparing and analyzing the technical characteristics of technologys of LPWAN.LoRa with low threshold for ad-hoc,has been chosen to study in thesis.LoRa has the characteristic of being able to communicate over long distances while maintaining low power consumption;multi-hop can successfully establish communication by using middle nodes to transmit data when the distance between the communication parties is too long or there are obstacles in the middle.Thesis proposes a LoRa mesh communication system that combines the characteristics of both,with long communication distance,low energy consumption,and using middle nodes.By comparing the of various multi hop routing algorithms.Flooding was adopted as the LoRa mesh routing algorithm.In order to solve the issues of data explosion and data duplication in the flooding.A series of optimization modifications were made to the flooding,including route establishment,node selection,setting of seq and ttl.Through tht simulation of matlab,it is concluded that compared with the traditional flooding,the optimized LoRa mesh routing algorithm has improved in throughput and transmission delay.Design the communication principle,system components,and data packet structure of LoRa mesh by Modbus.The implementation of LoRa mesh is achieved on both the software and hardware sides by incorporating embedded code into the hardware.Through actual operation and testing of the system’s performance,it has been shown that compared to transmission of single-hop,the LoRa mesh using transmission of multi-hop.Significantly improves the system’s throughput.Maintains good communication performance in the problem of over-long communication distances and obstacles of communication path.